The project ENTRANCE has the goal to investigate signal processing and system design methods that enable the design of flexible and power-efficient radio transmitters.

Motivation and Challenges
A special focus is digital predistortion for WLAN according to 802.11ac which includes larger bandwidths than 802.11n and requires advanced predistortion structures and learning algorithms. Optimization is used as a general tool for system design, as well as a method for structure and parameter learning of digital predistortion systems. Signal processing techniques are applied to the development and analysis of new measurement methods, which are highly important for the characterization of hardware building blocks and the calibration, adaptation and optimization of digital predistortion systems.

Focus and Results
The main results of ENTRANCE will be:

• A flexible system level simulator featuring digital/analog/RF co-simulation
• Structures for digital predistortion of wide-bandwidth 802.11ac signals
• Design tools for learning and optimizing digital predistortion structures
• Measurement methods for the characterization of RF and mixed-signal building blocks
• A study on emerging architectures for future digital-centric radio transmitters

Key Technologies

• WLAN 802.11ac
• Digital Predistortion
• Hardware-in-the-loop simulation and optimization

Benefits
By high-level simulation, possible problems can be identified in an early design stage, minimizing the risk and reducing the costs. Digital-centric design methods benefit from better technology scaling, improve the reusability and shorten the time-to-market. By use of digital enhancement like digital predistortion the performance and/or efficiency of RF power amplifiers is increased.